CVE-2023-53265
📋 TL;DR
This CVE describes a slab out-of-bounds read vulnerability in the Linux kernel's UBI (Unsorted Block Images) subsystem. The vulnerability occurs when the VID header offset plus its size exceeds the allocated memory area, potentially allowing attackers to read kernel memory. This affects systems using UBI with MTD devices, particularly in embedded Linux environments.
💻 Affected Systems
- Linux kernel
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
Kernel memory disclosure leading to information leakage, potential privilege escalation if combined with other vulnerabilities, or system crashes causing denial of service.
Likely Case
Information disclosure of kernel memory contents, potentially exposing sensitive data or system state information to attackers.
If Mitigated
Limited impact with proper kernel hardening and memory protection features enabled (like KASAN, SLAB_FREELIST_HARDENED).
🎯 Exploit Status
Exploitation requires local access and ability to trigger UBI operations. The vulnerability is a read-only OOB, making it primarily an information disclosure issue rather than direct code execution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commits: 1b42b1a36fc946f0d7088425b90d491b4257ca3e, 61aeba0e4b4124cfe3c5427feaf29c626dfa89e5, 61e04db3bec87f7dd10074296deb7d083e2ccade, 701bb3ed5a88a73ebbe1266895bdeff065226dca, 771e207a839a29ba943e89f473b0fecd16089e2e
Vendor Advisory: https://git.kernel.org/stable/c/1b42b1a36fc946f0d7088425b90d491b4257ca3e
Restart Required: Yes
Instructions:
1. Update to a kernel version containing the fix commits. 2. Check your distribution's security advisories for backported fixes. 3. Reboot the system after kernel update.
🔧 Temporary Workarounds
Disable UBI if not needed
linuxRemove or disable UBI module if not required for system operation
modprobe -r ubi
echo 'blacklist ubi' >> /etc/modprobe.d/blacklist.conf
🧯 If You Can't Patch
- Restrict access to UBI device nodes (e.g., /dev/ubi*) using file permissions or MAC systems like SELinux/AppArmor
- Enable kernel hardening features like KASAN, SLAB_FREELIST_HARDENED, and CONFIG_HARDENED_USERCOPY to detect/mitigate exploitation
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if UBI is loaded: 'uname -r' and 'lsmod | grep ubi'Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits or check with distribution-specific security tools📡 Detection & Monitoring
Log Indicators:
- Kernel logs showing KASAN slab-out-of-bounds warnings
- System crashes or panics related to UBI operations
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="kernel" AND ("KASAN: slab-out-of-bounds" OR "UBI" AND "panic" OR "Oops")🔗 References
- https://git.kernel.org/stable/c/1b42b1a36fc946f0d7088425b90d491b4257ca3e
- https://git.kernel.org/stable/c/61aeba0e4b4124cfe3c5427feaf29c626dfa89e5
- https://git.kernel.org/stable/c/61e04db3bec87f7dd10074296deb7d083e2ccade
- https://git.kernel.org/stable/c/701bb3ed5a88a73ebbe1266895bdeff065226dca
- https://git.kernel.org/stable/c/771e207a839a29ba943e89f473b0fecd16089e2e
- https://git.kernel.org/stable/c/846bfba34175c23b13cc2023c2d67b96e8c14c43
- https://git.kernel.org/stable/c/e1b73fe4f4c6bb80755eb4bf4b867a8fd8b1a7fe
- https://git.kernel.org/stable/c/f7adb740f97b6fa84e658892dcb08e37a31a4e77
